Apple's stock market value topped the $500 billion mark in early trading Wednesday, another record high for what was already the world's most valuable company.
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Despite its size, Apple is still one of the fastest growing technology companies. The company reported in January that its sales grew 73% last year. It also posted the second-most profitable quarter in history for a U.S. company.
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It was only a month ago that Apple's market valuation rose to $400 billion for the first time. On Jan. 25, it passed ExxonMobil (XOM, Fortune 500) as the most valuable company on the stock market.
http://money.cnn.com/2012/02/29/technology/apple_market_cap/index.htm
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